The stress and vascular catastrophes in newborn rats: mechanisms preceding and accompanying the brain hemorrhages

In this study, we analyzed the time-depended scenario of stress response cascade preceding and accompanying brain hemorrhages in newborn rats using an interdisciplinary approach based on: a morphological analysis of brain tissues, coherent-domain optical technologies for visualization of the cerebral blood flow, monitoring of the cerebral oxygenation and the deformability of red blood cells (RBCs). Using a model of stress-induced brain hemorrhages (sound stress, 120 dB, 370 Hz), we studied changes in neonatal brain 2, 4, 6, 8 h after stress (the pre-hemorrhage, latent period) and 24 h after stress (the post-hemorrhage period). We found that latent period of brain hemorrhages is accompanied by gradual pathological changes in systemic, metabolic, and cellular levels of stress. The incidence of brain hemorrhages is characterized by a progression of these changes and the irreversible cell death in the brain areas involved in higher mental functions. These processes are realized via a time-depended reduction of cerebral venous blood flow and oxygenation that was accompanied by an increase in RBCs deformability. The significant depletion of the molecular layer of the prefrontal cortex and the pyramidal neurons, which are crucial for associative learning and attention, is developed as a consequence of homeostasis imbalance. Thus, stress-induced processes preceding and accompanying brain hemorrhages in neonatal period contribute to serious injuries of the brain blood circulation, cerebral metabolic activity and structural elements of cognitive function. These results are an informative platform for further studies of mechanisms underlying stress-induced brain hemorrhages during the first days of life that will improve the future generation's health

A review of career devoted to biophotonics-in memoriam to Ekaterina Borisova (1978-2021)

Regretfully, because of her sudden demise, Assoc. Prof. Ekaterina Borisova is no longer amongst us. COVID-19 pulled away a brilliant scientist during the peak of her scientific career (see Fig. 1). All authors would like to express deepest condolences and sincere support to her family, friends, relatives and colleagues! We, therefore, rightfully commemorate her dedicated and devoted contribution to biophotonics, her readiness to always support, help, motivate and inspire all her colleagues and collaborators

Major and Trace Element Content of Tribulus terrestris L. Wildlife Plants

The genus Tribulus L. (Zygophyllaceae) includes 12 species, the most important of which is Tribulus terrestris L. This annual herb grows in temperate and tropical climates, and has a rich chemical composition of biologically active substances and chemical elements. Medicinal plants, and the phytopreparations obtained from them, are becoming more and more popular in world practice as they are used to successfully treat human diseases. Their therapeutic effect is due to the presence in them, of a variety of natural compounds and biologically important trace elements, especially in higher concentrations present in higher doses. T. terrestris is becoming more and more popular for the treatment of diseases of the human genital area and sexual dysfunctions. The elemental content in the tissues of leaf, flower, and fruit of T. terrestris was determined by using multi-element instrumental epithermal neutron activation analysis. For the first time, 26 essential and trace elements were observed in the plant species collected in Russia (from cultivated) and China (wild growing). It was confirmed that the elemental composition of T. terrestris grass varies depending on the habitat (geographic zones). The place of growth affects the accumulation of elements by the plant

Optical UV-VIS-NIR spectroscopy of benign, dysplastic and malignant cutaneous lesions ex vivo

Optical spectroscopic measurements with a few different modalities have been performed namely autofluorescence, transmission and diffuse reflectance spectroscopies in ultraviolet, visible and near-infrared spectral ranges. The investigated samples were cutaneous tumours ex vivo, obtained after surgical removal and kept in a formalin solution and histological sections from biopsy tissue samples, which were routinely processed for histological analysis. Comparative spectral data for benign, dysplastic nevi and pigmented malignant melanoma lesions, as well as for nonmelanoma skin tumour – basal cell carcinoma, squamous cell carcinoma and benign non-melanin pigmented pathologies – heamangioma and seboreic veruca are presented in the current report. Fluorescence spectra obtained reveal statistically significant differences between the different benign, dysplastic and malignant lesions by the level of emission intensity, as well by spectral shape, which are fingerprints applicable for differentiation algorithms. In reflectance and absorption modes the most significant differences are related to the influence of skin pigments – melanin and hemoglobin, less pronounced is the influence of structural proteins, such as collagen and keratin. Transmission spectroscopy mode gives complementary optical properties information about the tissue samples investigated to that one of reflectance and absorption spectroscopy

Photodynamic diagnostics of early gastric cancer: Complexity measures of gastric microcirculation and new model of metastatic adenocarcinoma of rat stomach

The detection of early gastric cancer that often develops asymptomatically is crucial for improving patient survival. The photodynamic diagnosis (PDD) of gastric cancer using 5-aminolevulinic acid/protoporphyrin IX (5-ALA/PpIX) has been reported in several studies. However, the selectivity of PDD of gastric tumor is poor with often false-positive results that require the development of new methods to improve PDD for early gastric cancer. Therefore, a measure of the complexity of gastric microcirculation (multi-scale entropy, MSE) and the detrended fluctuation analysis (DFA) were applied as additional tools to detect early gastric cancer in rats.In this experimental study, we used our original model of metastatic adenocarcinoma in the stomach of a rat. To induce a gastric tumor, we used a long-term combination (for 9 months, which is 1/2 of the life of rats) of two natural factors, such as chronic stress (overpopulation being typical for modern cities) and the daily presence of nitrites in food and drinks, which are common ingredients added to processed meat and fish to help preserve food. Our results clearly show that both methods, namely, PDD using 5-ALA/PpIX and complexity/correlation analysis, can detect early gastric cancer, which was confirmed by histological analysis. Pre-cancerous areas in the stomach were detected as an intermediate fluorescent signal or MSE level between normal and malignant lesions of the stomach. However, in some cases, PDD with 5-ALA/PpIX produced a false-positive fluorescence of exogenous fluorophores due to its accumulation in benign and inflammatory areas of the mucosa. This fact indicates that the PDD itself is not sufficient for the correct diagnosis of gastric cancer, and the use of additional characteristics, e.g., complexity measures or scaling exponents, can significantly improve the diagnostic accuracy of PDD of gastric cancer that should be confirmed in further clinical studies and applications